When to plant Sunflower in Sumner County County,
Sunflower planted in Sumner County County between April 11 and May 2 matures in 100 days — well before the October 26 first frost.
When to Plant Sunflower in Sumner County, KS
Sumner County, Kansas gardeners: here's your June plan
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Sumner County, Kansas.
Before July arrives, get these ready
- First harvests: sunflower
Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.
Sumner County, Kansas is in USDA Zone 7a. The average last spring frost is April 11 and the first fall frost is October 26, giving you a growing season of approximately 198 days.
At an elevation of 637 feet, Sumner County receives approximately 29 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Sunflower during the growing season.
Sumner County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.8
Drainage
Well Drained
Sunflower Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Sumner County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (6.4–7.8) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Sumner County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.6%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Jul 18 to harvest before frost.
Sunflower Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sunflower
Sunflower needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Sunflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 1.7" | 0.5" | 💧 Light watering |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Sumner County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Sunflower Planting Timeline — Sumner County, KS
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 21 | Mar 21 – Apr 4 |
| Transplant Outdoors | April 11 | Apr 11 – Apr 25 |
| Direct Sow | April 11 | Apr 11 – May 2 |
| Bloom | July 4 | Jul 4 – Oct 10 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
198 days in Sumner County
Growing Tips for Sunflower in Sumner County
Direct sow Sunflower outdoors after April 11 in Sumner County when soil has warmed and frost danger has passed.
Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Sumner County, KS?
Sumner County is in Zone 7a with an average last frost of April 11. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sumner County, KS?
Sumner County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 11 and first fall frost is October 26.
When should I plant Sunflower in Sumner County, ?
In Sumner County, , plant Sunflower after the last frost (around April 11) and before the first frost (around October 26). Best results when soil holds above 50°F.
What growing zone is Sumner County, for Sunflower?
Sumner County sits in USDA Zone 7a. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.
Can Sunflower grow in Sumner County's climate?
Yes — Sunflower grows well in Sumner County's temperate climate. Sumner County averages a 198-day frost-free season, with last frost around April 11 and first frost around October 26.
Your Sumner County Garden Planner — Free
A 22-page printable planner built for Sumner County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.